This invention relates to binders of the type that holds a plurality of loose leaves perforated along one edge for binding and, more particularly, to binders for loose-leaf albums, notebooks, clear-film-pouch files, and the like.
Binders that hold loose leaves with split rings opened and closed are brought under two chief categories; binders having proper rings for simply holding loose leaves in book form and binders holding loose leaves and secured to the back of a hard cover with eyelets or rivets.
Typical of the former category is, as shown in FIG. 1, a coil spring-like binder 1 that spirals through perforations 5 formed at regular intervals along one edge of a number of loose leaves 3. A variation is a binder 9, shown in FIG. 2, having partly open, almost completely closed binding rings 7.
The latter category with a cover, as represented in FIG. 3, typically comprises a cover 21, an elastic inner cover 11 fixed to the cover, a pair of movable back strips 13, 15 constrained by the inner cover to mate together along the inner edges, binding ring halves 17, 19 provided on the back strips to come into engagement for complete ring formation, and levers 23, 25 with which the back strips are urged upward or downward to allow the ring halves 17, 19 to open or close the rings. Another binder, as shown in FIG. 4, has a fixed back strip 27 secured to the inner side of a hard cover with rivets 28 and a movable back strip 29 which is turned open or close relative to the fixed strip with a pivot 31 so as to open or close split ring halves 33, 35, keeping the rings closed by means of a fixed lock member 37 and a pivotally movable lock member 39.
Binders of the designs illustrated in FIGS. 1 and 2 do not easily bind loose leaves; they cost money and time for binding. Moreover, the loose leaves cannot or can hardly be removed.
The designs shown in FIGS. 3 and 4 open and close easily to facilitate the binding and replacement of loose leaves. However, the binder of FIG. 3 comprises so many parts that it is large in size and costly. The much exposed levers 23, 25 and the inner cover 11 make the binder too bulky in sectional contour for services as depicted in FIGS. 1 and 2. The binder shown in FIG. 4 is complex in mechanism since it has a pivotal connection at the far end where the pivot 31 is located and has the lock members 37, 39 at the near end. If it is used unbacked as in FIGS. 1 or 2, the lock members are exposed, marring the appearance of the binder aesthetically.
It is therefore an object of the present invention to provide a binder extremely simple in construction, good in appearance, and easy to handle in binding and removing loose leaves.
Another object of the invention is to provide a binder structure suited for both applications backed by a cover and unbacked.